This is one of those games that make you sit back and say "is this really free?" It has created a very immersive 3d world in which you have to race with 8 other computer controlled ships over 6 different levels of play.
Ace Speeder is fast and furious and you will find it hard to stop playing.
One drawback is that it is in Japanese but it is simple to play. You press "Enter" at start-up and then you control the racer with the arrow keys and the spacebar (speed control).